Surrey became the first side to book their place at Finals Day after claiming a tense three-wicket victory over Somerset in a feisty Friends Life t20 quarter-final at the Kia Oval.
The South London county secured their semi-final place after overcoming a late wobble to chase down a 149 target with six balls to spare, thus denying Somerset a place at the 20-over showpiece for the first time in five years.
Surrey, the inaugural winners of the competition back in 2003, fought back well to restrict Somerset to 148-6 at the halfway stage.
Craig Kieswetter maintained his fine form in the tournament with an unbeaten 70, becoming the first player to pass 500 runs in the process, however only Peter Trego (33 off 26) provided any noteworthy support.
Somerset gloveman Kieswetter struck four boundaries and three towering sixes but had to be pulled apart by England team-mate Jade Dernbach after Gareth Batty had given Trego a send-off in the 13th over.
The wicket of Trego, bowled by Batty, sparked a Surrey rally which saw Somerset wilt from 99-1 to a modest total with Kieswetter, who reached his 50 in the 12th over, starved of the strike thereafter.
Jason Roy, who scored a century on his last competitive innings, and Steven Davies then propelled Surrey to a perfect reply -sharing a 62-run opening partnership to put the hosts ahead of the required run-rate.
It took a spectacular diving catch in the deep from Jos Buttler to remove Roy (28) off the bowling of Trego, who picked up Davies (35) in a similar fashion in his next over.
Surrey were 77-2 at the halfway stage but the match swung their way when Vikram Solanki hit George Dockrell for back-to-back sixes to leave 43 required from 42 balls.
Solanki departed in the 16th over with just 24 more needed, however his wicket unnerved Surrey, who lost Zander de Bruyn, Gary Wilson and Zafar Ansari with the finishing line in sight.
Veteran Jon Lewis sealed the win with a boundary, ensuring Somerset's disappointing season continues.